Stefnist or stfnist, an archaic term derived from stf, itself an obsolete abbreviation for sf, was Jack Speer's attempt at a replacement for the often misunderstood fan, but it didn't take. It's still used sometimes, especially by faanish fans, to refer to people who take a serious or scholarly (but not necessarily sercon) interest in science fiction, and who may or may not be part of the microcosm.

(Speer) - A suggested substitute for the word "fan", which has been favorably received. At this writing, however, a full vocabulary on the root has not been worked out, nor is general acceptance certain.